1PMT4121C/TR13

1PMT4121C/TR13 application field and working principle

Introduction

The 1PMT4121C/TR13 is a high-performance Zener diode manufactured and developed by ON Semiconductor. It is packaged as a single, small and robust SOD123 package. This package is intended for high-volume, automated placements

Application Field

The 1PMT4121C/TR13 is frequently encountered in industrial, military and medical applications due to its excellent performance. It is used for voltage regulation, over-voltage protection, or surge protection for sensitive circuitry. This Zener diode can be deployed in both PNP and NPN horizontal bipolar transistors.

Working Principle

The 1PMT4121C/TR13 diode works via a mechanism commonly known as ‘Zener breakdown’, which enables it to sustain accurate voltage regulation regardless of the load, temperature or current. This mechanism relies on an intense electric field in junction region of the diode. When a reverse voltage is applied across the Zener diode, free electrons on the n-layer are accelerated due to the intense electric field. Collisions between the electrons and the n-type nuclei create electron-hole pairs, which further increase the current flow in the diode. This phenomenon works as the electrical ‘breakdown’ of the diode.

In the reversed biased (or Zener) mode, a Zener diode\'s current is proportional to the applied voltage. This convenient property allows designers to set the Zener voltage to the target value using calibration resistors. The forward voltage drop is equal to the zener voltage. The voltage is maintained constant regardless of the load or current. This phenomenon is called ‘Zener Regulation’ and ensures accurately regulated voltage.

Conclusion

The 1PMT4121C/TR13 Zener diode boasts excellent performance, making it a popular choice for many industrial, medical and military applications. The device works via ‘Zener breakdown’, which allows it to sustain accurate voltage regulation regardless of the load, temperature or current. The ‘Zener Regulation’ principle allows designers to accurately regulate the applied voltage with this diode.